Quarter-turn fastening devices have been used in many environments for many purposes. In general, the operation of use includes the engagement between a spiral cam slot in a stud element and a cam follower or pin in a receptacle assembly. The pin follows the cam slot upon a quarter turn rotation into a locked or closed position. To permit the relative movement of the pin along the spiral cam slot a resilient member is employed so that the axial movement can be achieved and also to apply a biasing force when the members are in the locked position to help maintain the members in the locked position in rigid interengagement.
In certain environments it is desirable to have a flush exposed outer surface when two panels are fastened together. Of course, this is of concern where spring housings and springs are employed to attain the necessary bias and locking forces for the fastener elements. This situation is apparent when considering fasteners of similar design such as that disclosed in U.S. Pat. No. 3,594,876.
Consequently, in particular environments where a flush exposed surface is required, it is advantageous to provide a structural design which incorporates the operative elements of the fastener assembly behind the exposed surface of the outer panel. The structure must be such so as to not detract from the advantages of a quarter-turn fastener employing a spiral cam slot and pin arrangement with a spring biasing element for achieving the necessary locking tension. In fact, any increase in production in locking tension would naturally be an asset as well.